The present invention relates to an electromagnetic relay.
Conventionally, an electromagnetic relay in which an electromagnet block formed by winding a coil around an iron core with a spool interposed therebetween is magnetized or demagnetized to pivot a moving iron, which is supported pivotably by a yoke swaged and anchored to the iron core, and to drive a movable touch piece so that a movable contact opens and closes with respect to a fixed contact of a fixed touch piece arranged facing the movable touch piece is known (see e.g., Patent Document 1).
In this electromagnetic relay, a permanent magnet is arranged on an upper side of a contact switching unit to generate a magnetic field between the contacts so that when an arc current generates at the time of opening/closing of contact, the arc current can be extended toward the side and extinguished at an early stage.
Further, in the aforesaid convention electromagnetic relay, the magnetic field is generated by a single permanent magnet arranged on the upper side of the contact switching unit. The magnetic field is generated downward from a N pole (lower side) of the permanent magnet and is directed between the contacts toward the side, and thereafter directed towards the upper side, along each touch piece, to reach a S pole (upper side) of the permanent magnet. However, there is a problem that the magnetic flux easily leaks to the peripheral space and cannot be concentrated at the contact switching unit. As a result, the permanent magnet exerts a strong magnetic force which becomes necessary, which leads to higher cost.    Patent Document 1: Japanese Unexamined Patent Publication No. 2009-87918